There is something about South Carolina that was never quite understood. It was the first state in this cycle where Barack Obama's policies have been an abject failure: a unemployment level that is catastrophic, almost 10 percent, and a year-long effort to block Boeing from bringing 10,000 jobs to the area. That environment favored a candidate who will launch an unbridled attack on Obama's record and shortcomings, and who is undefensive about his own history. In the last week, that was Gingrich by a mile.

Going forward, the first disconcerting news for Romney is that there are a batch of other states that have the same alienated cast as South Carolina - the bevy of Southern states in March, the downcast industrial states with a substantial conservative white working class, and they are all prime territory for Gingrich's anti-elite message. The second bad news is that Romney's negatives with the national electorate are steadily climbing - in a few weeks, he may no longer be the more electable candidate, which means that the central rationale for his nomination will have collapsed.

As for Florida, Gingrich will be ahead there by the second half of next week, and the state that launched the tea party's most successful Senate candidate in 2010 can't be where Romney would want to make his next stand.

The past week - South Carolina notwithstanding - has been very sobering for Mitt Romney. He can still win the nomination, but only if he learns the lessons of his stumbles this past week.

Now that the tax return mini-scandal has contributed to one primary loss, Romney should release his tax returns. By not releasing his returns, he feeds suspicions that he has something to hide.

Romney is also going to have to work on developing an empathic persona. He is having a very difficult time connecting with voters. He has to figure out how to overcome the very effective job Newt Gingrich and Rick Perry did in tapping into anti-Wall Street sentiment among Republican voters (an effectiveness that was only amplified by the Romney camp bungling the tax return situation). Republican voters may not consider themselves part of the 99%, but they envision themselves as mom-and-pop entrepreneurs, not necessarily the 1%. As a card carrying member of the 1%, Romney is going to have to recast himself as more populist than elitist.

Playing hardball may help him burnish his populist credentials. The days of Romney’s trying to be the elder statesman and adopt a general election posture in a primary race are over. He’s going to have to stand up to the recent criticism and hit his opponents back hard. In his concession speech, he alluded to the fact that he would start personally drawing contrasts between him and Newt Gingrich. He now has to make good on his promise. If Romney doesn’t drive up his opponents’ negatives, voters will only remember why they don’t like him. Ironically, playing hardball might actually serve to humanize him and make him more accessible.

As long as there are GOP primary debates (and there are two of them scheduled before the Florida primary), Gov. Romney should indeed be running scared. Like a phoenix that has risen out of the ashes, Speaker Gingrich has twice now saved his campaign from defeat: once when his campaign imploded shortly after he announced his candidacy and again after he tumbled from his front-runner status less than a month before the Iowa caucus. Gingrich’s resilience is tied in large part to his debate performances. He has demonstrated a strong command of the issues during the debates. Even more importantly, he has tossed to conservatives the type of red meat (e.g., attacking the mainstream media) that strongly resonates with the base.

Gov. Romney rolled into South Carolina with momentum fresh from his New Hampshire win, with strong poll numbers, with superior resources, and with the backing of the state’s governor, Nikki Haley, who has ties to the tea party. Though Romney and his supporting super PACs outspent Gingrich in South Carolina, Gingrich was able to pull off a decisive victory – and Gingrich did so in the face of explosive allegations by his ex-wife that Gingrich had asked for an “open marriage.” There were many factors that led to Gingrich’s South Carolina win, but first among them was his most recent debate performances.

The next two debates could very well determine who wins the Florida primary. If Gingrich continues to perform well in the debates (and does not stumble otherwise), he could very well win Florida. However, even if Gingrich does win there, Romney has the resources and support to plough forward. Regardless of who wins Florida, Republicans should brace themselves for what could be a long and bruising primary season.

The hope by establishment Republicans that the nomination process would be a quick strike for their favorite son Mitt Romney has come to an end tonight. The inevitability preached by these supporters of the status quo has proven to be a myth. Mitt Romney is like a chameleon and has changed his positions on core conservative principles time and again. Conservatives in South Carolina rejected Romney tonight because they don't believe he's one of them, and I have full faith that the same will be true in the upcoming nominating contests. Conservatives are hungry for a nominee who holds their same principles and someone they can trust to stick to them when the going gets tough.

Mitt Romney suffers from the slow atrophy of high expectations. He's been the frontrunner for so long he's come to act like an old school incumbent instead of a fresh alternative to President Obama. He's been pro-business so long he missed the populist strains threading the tea party and occupy movements. He's been touting Bain so long he never saw the perceptions of vampire capitalism as a liability among Republicans. He's been moralizing rightward on abortion and equality so earnestly that he honestly never fathomed losing to a thrice-married adulterer. He's been defending Citizens United so long he didn't think what Super PACs might to to him not for him. He's been inevitable so long he didn't consider that his party might not want to fall in line.

Now that there is an entirely new campaign, it's time to throw out the old playbook, limber up, and move much more nimbly to his more populist opponents. Presidents must adjust to outside events all the time - so too their challengers.

Newt Gingrich won South Carolina for two reasons: one, because of his fiery shakedown of John King in the second debate and two, because apparently there's a big swinger voting bloc in the Palmetto State. South Carolina was definitely a wake-up call to Mitt Romney, especially on the heels of the Iowa primary going to Rick Santorum (which was a mere footnote due to Rick Perry's exit and Marianne Gingrich's open marriage allegations). But he's got a lot more money than Gingrich going forward and following the release (finally) of his tax returns, he'll be freer to call on Gingrich to release his Fannie Mae/Freddie Mac contract and to expound on his embarrassing ethics report.

Gingrich's head is always on the verge of exploding. Look for it to explode before Florida, cementing the belief that he is unelectable. Sure, Romney isn't "likable" or even "human" but at the end of the day, he's the Republicans' best shot of beating Obama.

Groundhog Day came early in South Carolina. Newt Gingrich's candidacy popped its head up from what seemed to be a deep hole into which he had dug himself with his philandering and arrogance.

Gingrich's victory in the South Carolina primary shows that for all their anti-gay, anti-women's rights, pro so-called family values rhetoric, Republicans care most about power for their own interests. If the earth really were flat, they would be rolling off the far right edge of it at this moment. Mitt Romney has never quite proved he's ready to go into that abyss, so he is in real danger of joining Florida's own Herman Cain on the sidelines after 1/31.

Romney should be running scared - of both Gingrich and Santorum, who mark my words will make some kind of unholy alliance to drive a stake into him in Florida. Endless money and even a tiny spoonful of voter common sense could yet save the day. But, no "sure thing" ever is. And so the fight goes on.

Romney is a pathetically weak "frontrunner," and has been from the beginning. The rapid rises of Bachmann, Perry, Cain, Santorum (in Iowa) and now Gingrich all have been more a manifestation of GOP voters' disaffection and lack of identification with Romney than a reflection of the intrinsic strengths of the particular candidate-of-the-month. South Carolina has voted for the eventual Republican nominee every time since 1980, and that's a historical precedent that should keep Mitt Romney from sleeping well tonight. The next polls in Florida should tell us whether Romney is in collapse or can still grind it out and win the nomination.

Romney should be calling all of his bundlers and soliciting money into Santorum's campaign to make sure Santorum stays alive. Otherwise Newt may well win Florida and then all bets are off.

In 2002, a few well-informed individuals supporting the re-election campaign of Sen. Tim Johnson (D-S.D.) understood that he probably couldn't get to 50 percent against John Thune and that he'd probably attracted as many indies as possible, but that Libertarian Kurt Evans could potentially draw an extra point or two from Thune's right flank. A few of these aforementioned individuals apparently organized a last minute effort to boost Evans, who ended up garnering 2,500 votes as Johnson edged Thune by 520 votes.

The dynamics are slightly different in a primary but the principles are the same. Santorum's approximately 10 percent in Florida/nationally are essentially off-limits to Mitt in a contested primary, unless somebody like Huntsman is the sole alternative. To win Florida, Mitt must prevent the conservative bloc, currently split between Newt and Santorum, from coalescing behind Newt. So Mitt must keep Santorum in the race. The best way to do that is money. And Mitt (and his homies from the real streets of America) have nothing if not mad benjamins.

It might seem crazy but it's perfectly legal and it's what Romney's people should be quietly communicating to their most sophisticated (and cynical) bundlers.

And hell, we're in the post-Citizens United age, so one of those bundlers - if his creative juices are flowing - could just decide to start his own PAC and just start running positive ads for Santorum in Florida to boost Santorum's #s there. Eliminate the middleman(ager) - that's the Bain way, right?

In sum, to borrow some Bain-style jargon: for Romney, in the absence of a very unlikely Santorum surge, the marginal benefit of an extra dollar spent boosting
Santorum is higher than another dollar spent attacking Newt or another dollar spent trying to boost Romney.

Florida won't provide a firewall for Romney. The state's voters can move dramatically - think water in a shallow pan - with changes in the media and tends to go with the "hot" candidate. This will work to Gingrich's advantage, especially in strongly conservative north Florida which looks a lot like South Carolina or Georgia. Romney is in serious trouble - along with the GOP's hopes for an early end to the nomination. Don't rule out an open convention and a dark horse nominee.

Three Republican primaries, there different winners. Of course Mitt Romney ought to be worried. South Carolina has long been a quirky state with its own mind (see 19th century nullification crisis and secession.) But Gingrich's victory reflects Romney vulnerabilities: no charisma; little fire in the belly; and doubts about his conservative credentials. The search for the un-Romney will continue a while longer until Republicans settle on what has been clear from the get go to all but the interminably obtuse: of the current Republican field, Romney has the best chance to beat Obama.

Walter DellingerAttorney, O'Melveny & Myers; former Office of Legal Counsel head and acting solicitor general :

Romney has major problems with conservatives that are not going away and may have gotten worse this week. Whatever happens in Florida this race will go on till Super Tuesday and there will be plenty of debates, maybe with one less participant, between now and then.

There are only two ways to run un-opposed or scared. Mitt has had an air of inevitability, he may be taking Newt too lightly. Newt orchestrated the first national congressional campaign in history. He is no joke and has a very good chance of winning the nomination.

Newt is flawed but fiery. Mitt is not trusted by the base but well-funded. This is a long way from being over.

Clearly inevitably was setting in for Team Romney and the candidate was getting sloppy and complacent. Romney still has a couple of weak spots (overall campaign message, inability to connect at debate podium) that need to be vastly improved.

Frankly Gingrich’s victory in South Carolina was the punch in the mouth Romney needed if he wants to win the nomination and be a strong general election candidate. While we are certainly in uncharted territory, this is still Romney’s nomination to lose given that the Florida nominating contest is followed by Nevada, and Gingrich failed to qualify for the Missouri and Virginia ballots.

Yes and no. Romney will likely be the ultimate winner of the Republican primary due to his financial and organizational advantage. He is the only candidate left who has a ground game and an infrastructure set up in most states, and he has money to spend. Gingrich is going to be reliant on his super PAC for money in the upcoming states and has barely a hint of an infrastructure set up.

That being said, Romney should be scared because Gingrich will be around for a lot longer now and that means more attacks are coming his way. This, to say the least, is not a good thing for Romney. Some argue that a prolonged primary campaign was a good thing for Obama in, but the attacks in 2008 and what we are seeing now are two different animals. The prolonged primary campaign ultimately helped Obama because he had to deal with attacks that were addressing his fundamental shortcoming in the eyes of most voters (his lack of experience). Since he was able to address this issue, he entered the general election a stronger candidate and was able to set aside this concern in the eyes of a majority of voters months before the election. If he had been relentlessly attacked by Clinton on Reverend Wright and Bill Ayers that would have been ultimately destructive to Obama's chances and would have been exactly what we are seeing happening in this year's GOP primary. If this pattern continues Romney likely will win, but he will be damaged goods when he crosses the finish line.

Again, Anybody But Romney won over Mitt Romney. Newt Gingrich is the latest embodiment of that sentiment among the GOP primary electorate. Gingrich , though, has scored the most decisive victory over Romney. If his numbers hold, Gingrich will defeat Romney by double digits. Romney's vote ceiling stills sits at or near 25 percent. Florida cannot just be a firewall for Romney; it'll have to be the graveyard for his opponents. And that ain't likely.

He doesn't win Florida decisively, we may as well stick a fork in Romney, he'll be done. If Newt wins Florida, the anti-Romney forces will coalesce nationally around him. In the delegate count, he will only trail Mitt by a handful of delegates. Romney will find out that money can't buy you love or votes. As Ron Paul pointed tonight, the nomination contest has barely selected 2% of the delegates. "It going to be a long slog," he reminded his supporters. Romney may be heartened by Paul's reality check.

While ARENA Democrats gleefully throw rocks at the Romney juggernaut, we forget that this time four years ago, Clinton and Obama were locked in a similar primary battle that lasted for months. The closeness of that contest very nearly cleaved the Democratic Party in two. The party reunited behind Barack Obama after the Denver convention. The GOP will probably do the same. But the extreme nature of the eventual GOP winner and the resulting party platform will augur well for President Obama's re-election. The starkly contrasting visions of America and the meanness of the GOP campaign against the president will turn the tide in Obama's favor.

Tonight wasn't just a crushing defeat for Mitt Romney but a body blow to the Republican establishment.

Mitt Romney started off in South Carolina with a 20-point lead and the conventional wisdom was that he'd close the deal on the nomination with three straight victories. Well it turns out Mitt has only won one state thus far and the more voters get to learn about the real Mitt Romney the more his support tanks.

Mitt's been exposed as a corporate raider with no core values who will do anything it takes to get ahead even if it means destroying American companies and slashing middle class jobs.

Whether it's his joke of a refusal to disclose his tax returns to lying about his jobs creation record and offshore investments in the Cayman Islands, Mitt continues to show he can't relate to working people.

Instead of being able to follow through on their hopes of being able to pop Champagne corks tonight, Mitt and the Republican establishment are now left having to worry about the road ahead.

Romney should be worried. He needs to translate the lessons learned from his loss today to results-driven changes to his campaign strategy, particularly: taking control of the agenda, turning Newt Gingrich¹s strengths into weaknesses, and negating the effects of his reluctances to publishing his tax returns. If he can do this successfully, he¹ll win Florida.

If the South Carolina exit polls are an indicator, Romney can bounce back if he aggressively hammers his electability and economic skills into the minds of voters. He has the organizational strength and money to still succeed but must match Gingrich¹s passion. Romney must connect with voters on an emotional-level. His propensity to come across as calculated and corporate is bringing diminishing returns to his campaign.

At the same time, it¹s should be no surprise that Gingrich won. Despite his recent surge, He was polling well in the state through mid December, scoring around 35%. His victory speaks a lot about his ability to recover. Gingrich is a contender.

The biggest winners today are the Republican Party and voters. The longer the race remains competitive, the more the party can engage a broad swath of the public in multiple upcoming primary states, and this larger pool of voters can have a meaningful say in determining the eventual nominee.

Mitt Romney still has many advantages in his quest for the presidential nomination. He has more money to spend than any other candidate. He has racked up more endorsements from Republican insiders (who remain notably cool to Gingrich). He has an organizational capacity that should allow him to compete nationally, while the contests following Florida look like friendly territory.

Florida itself fits Romney better than did Bible Belt-ish South Carolina. Evangelicals make up less of the GOP electorate, while affluent retirees compose more. The state's permissive absentee and early-voting rules favor Romney's stronger organization. Miami's powerful Cuban-American leadership backs Romney solidly. Florida is a huge and expensive state, which should favor Romney's deeper pockets. Yet Newt Gingrich should receive a powerful boost in the polls from his strong showing on Saturday, so I expect a close and intense contest. Keep an eye on Republican officeholders in Florida and elsewhere. Very few of them have endorsed Gingrich, and when he briefly threatened to win Iowa, numerous top Republicans made their scorn for the former Speaker clear. What do they do now?

Mitt Romney is in big trouble. First of all he lost the electability question to Newt Gingrich, according to South Carolina exit polls, by 10 points.

Second of all, the South Carolina Republicans don't want moderation, they want mean and nasty. And Gingrich was their man. To some extent, they are not alone in their party.

Third, Romney still has money and organization, but his inept mishandling of his tax returns, unforgiveable by a 1%er in this year of the 99%, is killing him two ways. He's painted as an out of touch elitist, and it makes his organization look Mickey Mouse.

Yes, Romney has reason to worry. The race that was supposed to be over is just getting warmed up, and the winner is not going to benefit from a long, bloody race.

Mitt Romney's performance in South Carolina should cause him major heartburn. Mitt and the Super PAC that supports him outspent Newt and his supporters nearly 2-to-1. He had a stronger campaign organization and was up by double-digits a mere week ago. He had endorsements from the governor of South Carolina, as well as the 2008 Republican primary winner in South Carolina, John McCain. His performance in the two debates and Newt's strong and powerful answers defined Newt as the true conservative warrior in South Carolina voter's mind. Romney will never be this person in the mind's of the current Republican base. Mitt even lost to Newt in exit polling of who would be the best candidate to take on President Obama.

Early voting started today in Florida. This will not help Mitt. However, Romney and the Super PAC that supports him have already spent and bought millions in expensive TV time in Florida. Gingrich and the Super PAC that supports him have spent $0. There are two debates this week in the Sunshine State.\

Romney must hold his own against Gingrich on these two nights or we might have a repeat of tonight in another southern state on the 31st. For Romney this can't happen. Florida is a winner-take-all state and it is Mitt's firewall. He must do well in Florida and he must put the fire out on the tax issue. Good thing for Romney...Newt doesn't do well as a frontrunner.

He absolutely should be running scared. Gingrich is going to get a ton of free press and if Santorum drops out he'll have another pool of support to increase his vote going forward. Romney has the money but now he looks beatable which means, at best, even if he does win the nomination, it's going to take a far longer nomination process.

The only person who has won each of these first three elections is Barack Obama. Democrats couldn't asked for a better, more fractured Republican party.

Romney has to be worried that Gingrich took 43 percent of the late deciding vote. Romney's admission that he only pays 15 percent of his income in federal taxes hurt him as did the leak that he has millions invested in the Cayman Islands. Those issues will continue to pose problems for Romney.

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